Digestion under saliva, simulated gastric and small intestinal conditions and fermentation in vitro by human intestinal microbiota of polysaccharides from Fuzhuan brick tea

- Digestion and fermentation of Fuzhuan brick tea polysaccharides (FBTPS) were investigated.
- FBTPS could pass through the digestive system and reach the large intestine safely.
- FBTPS was broken down and utilized by gut microbiota.
- FBTPS could significantly modulate the composition and abundance of gut microbiota.
- FBTPS could significantly enhance the production of short-chain fatty acids.

The aim of present study was to examine whether the digestive system (saliva, simulated gastric and small intestinal conditions) could break down and large intestinal microbiota could utilize the polysaccharides from Fuzhuan brick tea (FBTPS). The results showed that there was no change in molecular weight, monosaccharide content and content of reducing sugars before and after saliva, simulated gastric and small intestinal digestion, indicating that FBTPS could pass through the digestive system without being broken down and reach the large intestine safely. The content of carbohydrate was significantly decreased by fermentation in vitro of gut microbiota, suggesting that FBTPS could be broken down and utilized by gut microbiota. FBTPS could significantly modulate the composition and abundance of gut microbiota. Furthermore, the contents of short-chain fatty acids were significantly increased. Therefore, FBTPS is expected to be a functional food to improve human health and prevent disease through promoting the gut health.